The present invention is related to an intelligent equalizing battery charger having equalization charging circuitry, comprising an insulating switch-type DC to DC converting circuit, a microprocessor monitoring/calculating control circuit, and a charging battery set wherein the microprocessor monitoring/calculating control circuit, after the installment of the battery cells, can monitor the charging voltage and control the charging current during the whole charging process so that each cell of the battery set can be fully charged in equalization to achieve the best charging/discharging state thereby as well as to avoid the increase of the potential difference within the cells thereof, efficiently extending the battery life in application.
Please refer to FIG. 1. A conventional battery charger includes a charging circuitry 10 composed of a power supply switch circuit 11, a transformer 12, a rectification converting circuit, and a charging battery set 14. An AC power is supplied from the power input of the power supply switch circuit 11 to flow through a bridge rectifying circuit 111, a filtering capacitor 112 and a switch circuit 113. Then, the power supply is converted via the transformer 12 to feed a rectifying diode 131 of the rectifying convert circuit 13 and create a DC power supply that will pass through an output inductor 132 and a filtering capacitor 133 to provide the charging voltage required for the charging battery set 14 thereof.
There are some disadvantages to the above-mentioned conventional battery charger circuitry thereof. Most of all, in the charging process thereof, a charging voltage higher than the total voltage is supplied to the charging battery set 14 stringed in series, while each individual battery cell, characterized by a different rate of inner resistance after application, may require different charging voltage. As a result, the battery set 14 stringed in series for charging may become overcharged or undercharged in the process, which will cause the increase of the potential difference within the charging battery set 14 and, thus, reduce the lifespan of the battery in application.